You'll get an error like this one otherwise when the installer tries to compile the kernel modules needed by VMware (if you answer with yes and get the errors, that's no problem either - just read on):

Building the vmmon module.

Using 2.6.x kernel build system.
make: Entering directory `/tmp/vmware-config0/vmmon-only'
make -C /lib/modules/2.6.31-14-generic/build/include/.. SUBDIRS=$PWD SRCROOT=$PWD/. modules
make[1]: Entering directory `/usr/src/linux-headers-2.6.31-14-generic'
CC [M] /tmp/vmware-config0/vmmon-only/linux/driver.o
In file included from /tmp/vmware-config0/vmmon-only/./include/vmware.h:25,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:48:
/tmp/vmware-config0/vmmon-only/./include/vm_basic_types.h:104:7: warning: "__FreeBSD__" is not defined
In file included from /tmp/vmware-config0/vmmon-only/./include/x86.h:20,
from /tmp/vmware-config0/vmmon-only/./include/machine.h:24,
from /tmp/vmware-config0/vmmon-only/linux/driver.h:15,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:49:
/tmp/vmware-config0/vmmon-only/./include/x86apic.h:79:1: warning: "APIC_BASE_MSR" redefined
In file included from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/apic.h:11,
from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/smp.h:13,
from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/mmzone_64.h:12,
from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/mmzone.h:4,
from include/linux/mmzone.h:773,
from include/linux/gfp.h:4,
from include/linux/kmod.h:22,
from include/linux/module.h:13,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:12:
/usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/apicdef.h:133:1: warning: this is the location of the previous definition
In file included from /tmp/vmware-config0/vmmon-only/./include/x86.h:21,
from /tmp/vmware-config0/vmmon-only/./include/machine.h:24,
from /tmp/vmware-config0/vmmon-only/linux/driver.h:15,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:49:
/tmp/vmware-config0/vmmon-only/./include/x86desc.h:593:7: warning: "_MSC_VER" is not defined
In file included from /tmp/vmware-config0/vmmon-only/./include/machine.h:24,
from /tmp/vmware-config0/vmmon-only/linux/driver.h:15,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:49:
/tmp/vmware-config0/vmmon-only/./include/x86.h:830:1: warning: "PTE_PFN_MASK" redefined
In file included from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/paravirt.h:7,
from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/irqflags.h:61,
from include/linux/irqflags.h:57,
from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/system.h:11,
from /usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/processor.h:17,
from include/linux/prefetch.h:14,
from include/linux/list.h:6,
from include/linux/module.h:9,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:12:
/usr/src/linux-headers-2.6.31-14-generic/arch/x86/include/asm/pgtable_types.h:182:1: warning: this is the location of the previous definition
In file included from /tmp/vmware-config0/vmmon-only/./include/vcpuset.h:78,
from /tmp/vmware-config0/vmmon-only/./include/modulecall.h:22,
from /tmp/vmware-config0/vmmon-only/./common/vmx86.h:18,
from /tmp/vmware-config0/vmmon-only/linux/driver.h:16,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:49:
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:226:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:230:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:298:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:304:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:357:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:402:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:446:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:489:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:533:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:576:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:620:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:663:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:665:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:705:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:748:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:750:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:790:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:831:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:833:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:871:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:912:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:914:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:952:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:1073:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:1077:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:1124:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:1329:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:1454:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_atomic.h:1587:7: warning: "_MSC_VER" is not defined
In file included from /tmp/vmware-config0/vmmon-only/linux/driver.h:20,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:49:
/tmp/vmware-config0/vmmon-only/./include/compat_wait.h:37:5: warning: "VMW_HAVE_EPOLL" is not defined
/tmp/vmware-config0/vmmon-only/./include/compat_wait.h:43:5: warning: "VMW_HAVE_EPOLL" is not defined
In file included from /tmp/vmware-config0/vmmon-only/linux/driver.h:20,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:49:
/tmp/vmware-config0/vmmon-only/./include/compat_wait.h:60: error: conflicting types for â€˜poll_initwaitâ€™
include/linux/poll.h:70: note: previous declaration of â€˜poll_initwaitâ€™ was here
In file included from /tmp/vmware-config0/vmmon-only/./include/vm_asm_x86_64.h:23,
from /tmp/vmware-config0/vmmon-only/./include/vm_asm.h:28,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:52:
/tmp/vmware-config0/vmmon-only/./include/vm_asm_x86.h:430:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_asm_x86.h:676:7: warning: "_MSC_VER" is not defined
/tmp/vmware-config0/vmmon-only/./include/vm_asm_x86.h:716:7: warning: "_MSC_VER" is not defined
In file included from /tmp/vmware-config0/vmmon-only/./include/vm_asm.h:28,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:52:
/tmp/vmware-config0/vmmon-only/./include/vm_asm_x86_64.h:40:7: warning: "_MSC_VER" is not defined
In file included from /tmp/vmware-config0/vmmon-only/linux/vmhost.h:13,
from /tmp/vmware-config0/vmmon-only/linux/driver.c:71:
/tmp/vmware-config0/vmmon-only/./include/compat_semaphore.h:5:27: error: asm/semaphore.h: No such file or directory
/tmp/vmware-config0/vmmon-only/linux/driver.c:146: error: unknown field â€˜nopageâ€™ specified in initializer
/tmp/vmware-config0/vmmon-only/linux/driver.c:147: warning: initialization from incompatible pointer type
/tmp/vmware-config0/vmmon-only/linux/driver.c:150: error: unknown field â€˜nopageâ€™ specified in initializer
/tmp/vmware-config0/vmmon-only/linux/driver.c:151: warning: initialization from incompatible pointer type
/tmp/vmware-config0/vmmon-only/linux/driver.c: In function â€˜LinuxDriver_Ioctlâ€™:
/tmp/vmware-config0/vmmon-only/linux/driver.c:1650: error: â€˜struct task_structâ€™ has no member named â€˜euidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1650: error: â€˜struct task_structâ€™ has no member named â€˜uidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1651: error: â€˜struct task_structâ€™ has no member named â€˜fsuidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1651: error: â€˜struct task_structâ€™ has no member named â€˜uidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1652: error: â€˜struct task_structâ€™ has no member named â€˜egidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1652: error: â€˜struct task_structâ€™ has no member named â€˜gidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1653: error: â€˜struct task_structâ€™ has no member named â€˜fsgidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1653: error: â€˜struct task_structâ€™ has no member named â€˜gidâ€™
/tmp/vmware-config0/vmmon-only/linux/driver.c:1670: error: too many arguments to function â€˜smp_call_functionâ€™
make[2]: *** [/tmp/vmware-config0/vmmon-only/linux/driver.o] Error 1
make[1]: *** [_module_/tmp/vmware-config0/vmmon-only] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-2.6.31-14-generic'
make: *** [vmmon.ko] Error 2
make: Leaving directory `/tmp/vmware-config0/vmmon-only'
Unable to build the vmmon module.

For more information on how to troubleshoot module-related problems, please
visit vmware site at "http://www.vmware.com/download/modules/modules.html" and
"http://www.vmware.com/support/reference/linux/prebuilt_modules_linux.html".